Fig. 1. Supranuclear oculomotor system. Conjugate horizontal gaze to left originates in right frontal optomotor cortex (R). Pathway descends in area of internal capsule, decussates at level of trochlear nucleus (IV) to synapse in left pontine paramedian reticular formation (PPRF). Via direct connection to abducens nucleus (VI; labeled on right side), left lateral rectus (LR is innervated. From abducens nucleus via contralateral medial longitudinal fasciculus (MLF) impulse is directed to contralateral oculomotor nuclear complex (III; labeled on left side), then to right medial rectus (MR). (VN, vestibular nuclear complex; SCC, semicircular canals)